PLGA Nanoparticle Formation Based on Formulae Incorporating Different Proportions of DOTAP

The polymer poly(lactic-co-glycolic acid) (PLGA) emulsifies in aqueous conditions to form nanoparticles. Such vesicles are frequently involved in drug delivery, of vaccines for instance, due to several advantages, such as high structural stability, low cytotoxicity and biodegradability. Incorporating lipids onto surfaces of such nanoparticles enhances their effectiveness in cellular internalization. However, the effects on structural integrity in terms of the entire polymer-lipid particle of incorporating lipids onto polymeric nanoparticles is rather less fathomed. In this article we synthesized PLGA vesicles via ultrasonication of suspensions of PLGA as the hydrophobic phase, deionized (DI) water as the inner aqueous phase, and 30% ethanol as the outer aqueous phase. The hydrophobic phase was pre-added 1,2-dioleoyl-3-trimethylammonium propane (DOTAP) in different ratios. The resulting vesicles were presented with scan electron micrographs (SEMs), and were measured their sizes and zeta-potentials. Average zeta potential increased as proportion of lipid to polymer increased, while in all samples there were polydispersion, suggesting the possibility of nanoparticles dissembled. We suggest that the ratio leading to the highest average zeta potential is within the interval between 1:6 and 1:4, or greater than 1:4.